Apple's update of their search tool, Sherlock, is set to worry Amazon, Barnes & Noble, eBay and other online merchants by providing automatic comparison shopping across sites.

Sherlock II - part of the upcoming OS9 release - compares prices and availability of a given product across competing sites, providing a simple aggregation service.

Naturally, the merchants are upset at the thought at being beaten at their own online game - many online merchants offering associate deals insist on exclusivity, barring aggregators from the market.

eBay are further upping the ante by objecting to Sherlock's ability to track the progress of auctions, as they have done with similar standalone sites and production such as AuctionWatch.

OS9 is the 5th sizeable upgrade to the Macintosh operating system since Apple emerged last year from the OS doldrums which Microsoft appear to be struggling in as they work towards the disappearing-over-the-horizon release of Windows 2000.